package com.fanvil.videoconference;

import android.annotation.SuppressLint;
import android.graphics.RectF;
import android.graphics.SurfaceTexture;
import android.opengl.GLES11Ext;
import android.opengl.GLES20;
import android.opengl.Matrix;
import android.os.Looper;
import android.util.Log;
import android.util.Pair;
import android.util.Size;
import android.view.Surface;

import java.io.BufferedReader;
import java.io.DataInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.InputStreamReader;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.FloatBuffer;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;

import com.fanvil.videoconference.FvlLogger;
import com.fanvil.videoconference.FvlSystemProperties;

@SuppressLint("InlinedApi")
public class FvlTextureManager {
    private static FvlLogger sLogger =
        FvlLogger.getLogger(FvlTextureManager.class.getSimpleName(), FvlLogger.DEBUG);

    private static final boolean DEBUG = false;

    private static final int FLOAT_SIZE_BYTES = 4;
    private static final int TRIANGLE_VERTICES_DATA_STRIDE_BYTES = 5 * FLOAT_SIZE_BYTES;
    private static final int TRIANGLE_VERTICES_DATA_POS_OFFSET = 0;
    private static final int TRIANGLE_VERTICES_DATA_UV_OFFSET = 3;
    private final float[] mTriangleVerticesData = {
            // X, Y, Z, U, V
            -1.0f, -1.0f, 0, 0.f, 0.f,
            1.0f, -1.0f, 0, 1.f, 0.f,
            -1.0f,  1.0f, 0, 0.f, 1.f,
            1.0f,  1.0f, 0, 1.f, 1.f,
    };

    private FloatBuffer mTriangleVertices;

    private static final String VERTEX_SHADER =
            "uniform mat4 uMVPMatrix;\n" +
                    "uniform mat4 uSTMatrix;\n" +
                    "attribute vec4 aPosition;\n" +
                    "attribute vec4 aTextureCoord;\n" +
                    "varying vec2 vTextureCoord;\n" +
                    "void main() {\n" +
                    "  gl_Position = uMVPMatrix * aPosition;\n" +
                    "  vTextureCoord = (uSTMatrix * aTextureCoord).xy;\n" +
                    "}\n";

    private static final String FRAGMENT_SHADER =
            "#extension GL_OES_EGL_image_external : require\n" +
                    "precision mediump float;\n" +      // highp here doesn't seem to matter
                    "varying vec2 vTextureCoord;\n" +
                    "uniform samplerExternalOES sTexture;\n" +
                    "void main() {\n" +
                    "  gl_FragColor = texture2D(sTexture, vTextureCoord);\n" +
                    "}\n";

    private float[] mMVPMatrix = new float[16];
    private float[] mSTMatrix = new float[16];

    public static final int VIEW_ROLE_INVALID = -1;
    public static final int VIEW_ROLE_LOCAL = 0;
    public static final int VIEW_ROLE_REMOTE = 1;

    private static final int LANDSCAPE = 0;
    private static final int PORTRAIT = 1;

    private int mViewRole = VIEW_ROLE_INVALID;
    private int mViewWidth = -1;
    private int mViewHeight = -1;
    private int mVideoWidth = -1;
    private int mVideoHeight = -1;
    private boolean mUpdateMatrix = false;

    private String mName = null;

    private int mProgram;
    private int mTextureID = -12345;
    private int muMVPMatrixHandle;
    private int muSTMatrixHandle;
    private int maPositionHandle;
    private int maTextureHandle;

    //vbo id
    private int vboId;

    private SurfaceTexture mSurfaceTexture = null;

    private FvlVideoLayout mVideoLayout = null;

    public FvlTextureManager() {
        mName = "unknown";
        if (sLogger.isLoggable()) sLogger.v("[" + mName + "] FvlTextureManager Created");
        init();
    }

    public FvlTextureManager(String name) {
        mName = name;
        if (sLogger.isLoggable()) sLogger.v("[" + mName + "] FvlTextureManager Created");
        init();
    }

    private void init() {
        mTriangleVertices = ByteBuffer.allocateDirect(
                mTriangleVerticesData.length * FLOAT_SIZE_BYTES)
                .order(ByteOrder.nativeOrder()).asFloatBuffer();
        mTriangleVertices.put(mTriangleVerticesData).position(0);

        Matrix.setIdentityM(mSTMatrix, 0);

        mVideoLayout = FvlVideoLayout.getInstance();
    }

    public boolean isReady() {
        return mProgram != 0;
    }

    public int getTextureId() {
        if (sLogger.isLoggable()) sLogger.v("[" + mName + "] getTextureId=" + mTextureID);
        return mTextureID;
    }

    public boolean isTexture(int texId) {
        return GLES20.glIsTexture(texId);
    }

    public int generateTexture() {
        int[] textures = new int[1];
        GLES20.glGenTextures(1, textures, 0);
        checkGlError("glGenTextures");
        return textures[0];
    }

    public void deleteTexture(int texId) {
        int[] textures = new int[] { texId };
        assertNonUiThread("glDeleteTextures");
        GLES20.glDeleteTextures(1, textures, 0);
        checkGlError("glDeleteTextures");
    }

    public SurfaceTexture getSurfaceTexture() {
        if (sLogger.isLoggable()) sLogger.v("[" + mName + "] getSurfaceTexture=" + mSurfaceTexture);
        if (mSurfaceTexture != null && mVideoWidth > 0 && mVideoHeight > 0) {
            if (sLogger.isLoggable()) sLogger.v("[" + mName + "] getSurfaceTexture=" + mVideoWidth + "x" +mVideoHeight);
            mSurfaceTexture.setDefaultBufferSize(mVideoWidth, mVideoHeight);
        }
        return mSurfaceTexture;
    }

    public void setVideoSize(int videoW, int videoH) {
        if (sLogger.isLoggable()) sLogger.v("[" + mName + "] setVideoSize: " + videoW + "X" + videoH);
        mVideoWidth = videoW;
        mVideoHeight = videoH;
        mUpdateMatrix = true;
    }

    public void setViewSize(int viewW, int viewH) {
        if (sLogger.isLoggable()) sLogger.v("[" + mName + "] setViewSize: " + viewW + "X" + viewH);
        mViewWidth = viewW;
        mViewHeight = viewH;
        mUpdateMatrix = true;
    }

    public void setViewRole(int role) {
        if (sLogger.isLoggable()) sLogger.v("[" + mName + "] setViewRole: " + role);
        mViewRole = role;
        mUpdateMatrix = true;
    }

    public void updateFrame() {
        if (mSurfaceTexture == null) {
            throw new RuntimeException("SurfaceTexture is null");
        }
        mSurfaceTexture.updateTexImage();
    }

    public void updateTransform(SurfaceTexture texture) {
        if (texture != null) {
            texture.getTransformMatrix(mSTMatrix);
        }
    }

    public void drawFrame() {
        checkGlError("onDrawFrame start");

        if (mUpdateMatrix) {
            mUpdateMatrix = false;

            GLES20.glViewport(0, 0, mViewWidth, mViewHeight);
            updateRatio(mViewWidth, mViewHeight, mVideoWidth, mVideoHeight);
        }

        //mSurfaceTexture.getTransformMatrix(mSTMatrix);

        //GLES20.glClearColor(0.0f, 1.0f, 0.0f, 1.0f);
        //GLES20.glClear(GLES20.GL_DEPTH_BUFFER_BIT | GLES20.GL_COLOR_BUFFER_BIT);

        GLES20.glUseProgram(mProgram);
        checkGlError("glUseProgram");

        GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
        GLES20.glBindTexture(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, 0);
        GLES20.glBindTexture(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, mTextureID);

        mTriangleVertices.position(TRIANGLE_VERTICES_DATA_POS_OFFSET);
        GLES20.glVertexAttribPointer(maPositionHandle, 3, GLES20.GL_FLOAT, false,
                TRIANGLE_VERTICES_DATA_STRIDE_BYTES, mTriangleVertices);
        checkGlError("glVertexAttribPointer maPosition");
        GLES20.glEnableVertexAttribArray(maPositionHandle);
        checkGlError("glEnableVertexAttribArray maPositionHandle");

        mTriangleVertices.position(TRIANGLE_VERTICES_DATA_UV_OFFSET);
        GLES20.glVertexAttribPointer(maTextureHandle, 2, GLES20.GL_FLOAT, false,
                TRIANGLE_VERTICES_DATA_STRIDE_BYTES, mTriangleVertices);
        checkGlError("glVertexAttribPointer maTextureHandle");
        GLES20.glEnableVertexAttribArray(maTextureHandle);
        checkGlError("glEnableVertexAttribArray maTextureHandle");


        //Matrix.setIdentityM(mMVPMatrix, 0);
        GLES20.glUniformMatrix4fv(muMVPMatrixHandle, 1, false, mMVPMatrix, 0);
        GLES20.glUniformMatrix4fv(muSTMatrixHandle, 1, false, mSTMatrix, 0);

        //useVboDraw();
/*
        //1. 绑定VBO
        GLES20.glBindBuffer(GLES20.GL_ARRAY_BUFFER, vboId);
        //2. 设置顶点数据
        mTriangleVertices.position(TRIANGLE_VERTICES_DATA_POS_OFFSET);
        GLES20.glVertexAttribPointer(maPositionHandle, 3, GLES20.GL_FLOAT, false,
                TRIANGLE_VERTICES_DATA_STRIDE_BYTES, mTriangleVertices);
        checkGlError("glVertexAttribPointer maPosition");
        GLES20.glEnableVertexAttribArray(maPositionHandle);
        checkGlError("glEnableVertexAttribArray maPositionHandle");

        mTriangleVertices.position(TRIANGLE_VERTICES_DATA_UV_OFFSET);
        GLES20.glVertexAttribPointer(maTextureHandle, 2, GLES20.GL_FLOAT, false,
                TRIANGLE_VERTICES_DATA_STRIDE_BYTES, mTriangleVertices);
        checkGlError("glVertexAttribPointer maTextureHandle");
        GLES20.glEnableVertexAttribArray(maTextureHandle);
        checkGlError("glEnableVertexAttribArray maTextureHandle");

*/

        GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4);
        checkGlError("glDrawArrays");
        GLES20.glFinish();

        //3. 解绑VBO
        //GLES20.glBindBuffer(GLES20.GL_ARRAY_BUFFER, 0);
    }

    /**
     * Call this after the EGL surface has been created and made current.
     */
    public SurfaceTexture createTexture() {
        if (sLogger.isLoggable()) sLogger.v("[" + mName + "] createTexture");
        if (mSurfaceTexture == null) {
            int[] textures = new int[1];
            GLES20.glGenTextures(1, textures, 0);

            mTextureID = textures[0];

            mSurfaceTexture = new SurfaceTexture(mTextureID);
            if (sLogger.isLoggable()) sLogger.v("[" + mName + "] SurfaceTexture created, mTextureID=" + mTextureID);
        }
        return mSurfaceTexture;
    }

    public void releaseTexture() {
        if (sLogger.isLoggable()) sLogger.v("[" + mName + "] releaseTexture");
        if (mSurfaceTexture != null) {
            mSurfaceTexture.release();
            mSurfaceTexture = null;
        }
        mTextureID = -12345;
    }

    /**
     * Initializes GL state.  Call this after the EGL surface has been created and made current.
     */
    public void setup() {
        if (sLogger.isLoggable()) sLogger.v("[" + mName + "] setup");

        mProgram = createProgram(VERTEX_SHADER, FRAGMENT_SHADER);
        if (mProgram == 0) {
            throw new RuntimeException("failed creating program");
        }
        maPositionHandle = GLES20.glGetAttribLocation(mProgram, "aPosition");
        checkGlError("glGetAttribLocation aPosition");
        if (maPositionHandle == -1) {
            throw new RuntimeException("Could not get attrib location for aPosition");
        }
        maTextureHandle = GLES20.glGetAttribLocation(mProgram, "aTextureCoord");
        checkGlError("glGetAttribLocation aTextureCoord");
        if (maTextureHandle == -1) {
            throw new RuntimeException("Could not get attrib location for aTextureCoord");
        }

        muMVPMatrixHandle = GLES20.glGetUniformLocation(mProgram, "uMVPMatrix");
        checkGlError("glGetUniformLocation uMVPMatrix");
        if (muMVPMatrixHandle == -1) {
            throw new RuntimeException("Could not get attrib location for uMVPMatrix");
        }

        muSTMatrixHandle = GLES20.glGetUniformLocation(mProgram, "uSTMatrix");
        checkGlError("glGetUniformLocation uSTMatrix");
        if (muSTMatrixHandle == -1) {
            throw new RuntimeException("Could not get attrib location for uSTMatrix");
        }

        //createVBO();

        mTextureID = generateTexture();
        if (sLogger.isLoggable()) sLogger.v("[" + mName + "] setup: TextureID=" + mTextureID);
        GLES20.glBindTexture(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, mTextureID);
        checkGlError("glBindTexture mTextureID");

        GLES20.glTexParameterf(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, GLES20.GL_TEXTURE_MIN_FILTER,
                GLES20.GL_NEAREST);
        GLES20.glTexParameterf(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, GLES20.GL_TEXTURE_MAG_FILTER,
                GLES20.GL_LINEAR);
        GLES20.glTexParameteri(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, GLES20.GL_TEXTURE_WRAP_S,
                GLES20.GL_CLAMP_TO_EDGE);
        GLES20.glTexParameteri(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, GLES20.GL_TEXTURE_WRAP_T,
                GLES20.GL_CLAMP_TO_EDGE);
        checkGlError("glTexParameter");
    }

    public void release() {
        if (sLogger.isLoggable()) sLogger.v("[" + mName + "] release");
        /*if (mSurfaceTexture != null) {
            mSurfaceTexture.release();
            mSurfaceTexture = null;
        }*/
        deleteTexture(mTextureID);
        mTextureID = -12345;
        if (mProgram != 0) {
            GLES20.glDeleteProgram(mProgram);
            mProgram = 0;
        }
    }

    /**
     * Replaces the fragment shader.  Pass in null to reset to default.
     */
    public void changeFragmentShader(String fragmentShader) {
        if (fragmentShader == null) {
            fragmentShader = FRAGMENT_SHADER;
        }
        GLES20.glDeleteProgram(mProgram);
        mProgram = createProgram(VERTEX_SHADER, fragmentShader);
        if (mProgram == 0) {
            throw new RuntimeException("failed creating program");
        }
    }

    private int loadShader(int shaderType, String source) {
        int shader = GLES20.glCreateShader(shaderType);
        checkGlError("glCreateShader type=" + shaderType);
        GLES20.glShaderSource(shader, source);
        GLES20.glCompileShader(shader);
        int[] compiled = new int[1];
        GLES20.glGetShaderiv(shader, GLES20.GL_COMPILE_STATUS, compiled, 0);
        if (compiled[0] == 0) {
            if(sLogger.isLoggable()) sLogger.e("Could not compile shader " + shaderType + ":");
            if(sLogger.isLoggable()) sLogger.e(" " + GLES20.glGetShaderInfoLog(shader));
            GLES20.glDeleteShader(shader);
            shader = 0;
        }
        return shader;
    }

    private void createVBO() {
        //1. 创建VBO
        int[] vbos = new int[1];
        GLES20.glGenBuffers(vbos.length, vbos, 0);
        vboId = vbos[0];
        //2. 绑定VBO
        GLES20.glBindBuffer(GLES20.GL_ARRAY_BUFFER, vboId);
        //3. 分配VBO需要的缓存大小
        GLES20.glBufferData(GLES20.GL_ARRAY_BUFFER, mTriangleVerticesData.length * 4, mTriangleVertices, GLES20.GL_STATIC_DRAW);
        //4. 为VBO设置顶点数据的值
        //GLES20.glBufferSubData(GLES20.GL_ARRAY_BUFFER, 0, mTriangleVerticesData.length * 4, mTriangleVertices);
        //GLES20.glBufferSubData(GLES20.GL_ARRAY_BUFFER, vertexData.length * 4, textureData.length * 4, textureBuffer);
        //5. 解绑VBO
        GLES20.glBindBuffer(GLES20.GL_ARRAY_BUFFER, 0);
    }

    private void useVboDraw() {
        //1. 绑定VBO
        GLES20.glBindBuffer(GLES20.GL_ARRAY_BUFFER, vboId);
        //2. 设置顶点数据
        mTriangleVertices.position(TRIANGLE_VERTICES_DATA_POS_OFFSET);
        GLES20.glVertexAttribPointer(maPositionHandle, 3, GLES20.GL_FLOAT, false,
                TRIANGLE_VERTICES_DATA_STRIDE_BYTES, mTriangleVertices);
        checkGlError("glVertexAttribPointer maPosition");
        GLES20.glEnableVertexAttribArray(maPositionHandle);
        checkGlError("glEnableVertexAttribArray maPositionHandle");

        mTriangleVertices.position(TRIANGLE_VERTICES_DATA_UV_OFFSET);
        GLES20.glVertexAttribPointer(maTextureHandle, 2, GLES20.GL_FLOAT, false,
                TRIANGLE_VERTICES_DATA_STRIDE_BYTES, mTriangleVertices);
        checkGlError("glVertexAttribPointer maTextureHandle");
        GLES20.glEnableVertexAttribArray(maTextureHandle);
        checkGlError("glEnableVertexAttribArray maTextureHandle");

        //3. 解绑VBO
        GLES20.glBindBuffer(GLES20.GL_ARRAY_BUFFER, 0);
    }

    private int createProgram(String vertexSource, String fragmentSource) {
        int vertexShader = loadShader(GLES20.GL_VERTEX_SHADER, vertexSource);
        if (vertexShader == 0) {
            return 0;
        }
        int pixelShader = loadShader(GLES20.GL_FRAGMENT_SHADER, fragmentSource);
        if (pixelShader == 0) {
            return 0;
        }

        int program = GLES20.glCreateProgram();
        checkGlError("glCreateProgram");
        if (program == 0) {
            if(sLogger.isLoggable()) sLogger.e("Could not create program");
        }
        GLES20.glAttachShader(program, vertexShader);
        checkGlError("glAttachShader");
        GLES20.glAttachShader(program, pixelShader);
        checkGlError("glAttachShader");
        GLES20.glLinkProgram(program);
        int[] linkStatus = new int[1];
        GLES20.glGetProgramiv(program, GLES20.GL_LINK_STATUS, linkStatus, 0);
        if (linkStatus[0] != GLES20.GL_TRUE) {
            if(sLogger.isLoggable()) sLogger.e("Could not link program: ");
            if(sLogger.isLoggable()) sLogger.e(GLES20.glGetProgramInfoLog(program));
            GLES20.glDeleteProgram(program);
            program = 0;
        }

        GLES20.glDeleteShader(vertexShader);
        GLES20.glDeleteShader(pixelShader);
        return program;
    }

    public void checkGlError(String op) {
        int error;
        while ((error = GLES20.glGetError()) != GLES20.GL_NO_ERROR) {
            if(sLogger.isLoggable()) sLogger.e(op + ": glError " + error);
            throw new RuntimeException(op + ": glError " + error);
        }
    }

    /**
     * Make sure we are not operating in the UI thread.
     *
     * It is often tricky to track down bugs that happen when issuing GL commands in the UI thread.
     * This is especially true when releasing GL resources. Often this will cause errors much later
     * on. Therefore we make sure we do not do these dangerous operations on the UI thread.
     */
    private void assertNonUiThread(String operation) {
        if (Looper.getMainLooper().getThread() == Thread.currentThread()) {
            throw new RuntimeException("Attempting to perform GL operation '" + operation
                    + "' on UI thread!");
        }
    }

    private void updateRatio(int viewWidth, int viewHeight, int videoWidth, int videoHeight) {
        float widthRatio = 1.0f;
        float heightRatio = 1.0f;
        int orientation = LANDSCAPE;
        Pair<Float, Float> videoRatio;

        if (viewWidth <= 0 || viewHeight <= 0 || videoWidth <= 0 || videoHeight <= 0) {
            sLogger.e("[" + mName + "] updateRatio: invalid size  viewWidth=" + viewWidth + " viewHeight=" + viewHeight
                     + " videoWidth=" + videoWidth + " videoHeight=" + videoHeight);
            return;
        }

        if (sLogger.isLoggable()) sLogger.v("[" + mName + "] updateRatio VideoSize=" + videoWidth + "X" + videoHeight);
        if (sLogger.isLoggable()) sLogger.v("[" + mName + "] updateRatio ViewSize=" + viewWidth + "X" + viewHeight);
        if (sLogger.isLoggable()) sLogger.v("[" + mName + "] updateRatio WidthRatio=" + widthRatio
                + " HeightRatio=" + heightRatio);

        videoRatio = mVideoLayout.getVideoRatio(mViewRole, mViewWidth, mViewHeight, mVideoWidth, mVideoHeight);
        if (videoRatio != null) {
            widthRatio = videoRatio.first;
            heightRatio = videoRatio.second;
            if (sLogger.isLoggable()) sLogger.v("[" + mName + "] updateRatio WidthRatio=" + widthRatio
                    + " HeightRatio=" + heightRatio);
            orientation = viewWidth > viewHeight ? LANDSCAPE : PORTRAIT;
            orthoMatrix(widthRatio, heightRatio, orientation);
        }
    }

    private void scaleMatrix(float sx, float sy) {
        if (sLogger.isLoggable()) sLogger.v("[" + mName + "] scaleMatrix sx=" + sx + " sy=" + sy);
        Matrix.scaleM(mMVPMatrix, 0, sx, sy, 1f);
    }

    private void orthoMatrix(float widthRatio, float heightRatio, int orientation) {
        float[] projectMatrix = new float[] {
                1, 0, 0, 0,
                0, 1, 0, 0,
                0, 0, 1, 0,
                0, 0, 0, 1,
        };

        float[] viewMatrix = new float[16];

        Matrix.setIdentityM(projectMatrix, 0);
        if (sLogger.isLoggable()) sLogger.v("[" + mName + "] orthoMatrix WidthRatio=" + widthRatio
                + " HeightRatio=" + heightRatio + " Orientation=" + orientation);
        if(orientation == LANDSCAPE) {
            Matrix.orthoM(projectMatrix, 0, -widthRatio,widthRatio, -1,1, 3, 7);
        } else if (orientation == PORTRAIT) {
            Matrix.orthoM(projectMatrix, 0, -1, 1, -heightRatio, heightRatio,3, 7);
        }

        Matrix.setIdentityM(viewMatrix, 0);
        Matrix.setLookAtM(viewMatrix, 0, 0, 0, 7.0f, 0f, 0f, 0f, 0f, 1.0f, 0.0f);

        Matrix.setIdentityM(mMVPMatrix, 0);
        Matrix.multiplyMM(mMVPMatrix,0,projectMatrix,0,viewMatrix,0);
    }
}

